I had briefly mentioned Belphigor's Prime in a linkdump seven years ago, then found it again today while looking for something else, and decided it was worth reposting.
Belphegor's prime is the palindromic prime number 1000000000000066600000000000001, a number which reads the same both backwards and forwards and is only divisible by itself and one...The number itself contains superstitious elements that have given it its name: the number 666 at the heart of Belphegor's prime is widely associated as being the number of the beast... This number is surrounded on either side by thirteen zeroes and is 31 digits in length (thirteen reversed)...In the short scale, this number would be named "one nonillion, sixty-six quadrillion, six hundred trillion one".
Useful information for filling in any awkward conversation gaps during Halloween parties. The symbol for it is an inverted pi.
I'm not sure what's so special about that. Aren't there an infinite number of palindromic primes with 666 at their center?
ReplyDeleteThe number is less interesting in hexadecimal: 0xC9F2C9CD047618A431E0A8001. Twenty-five digits and no thirteens. Not very interesting in octal, either: 01447626234640435414244143602500001. I conclude that the interesting attributes are a but quirk of decimal encoding.
ReplyDeleteI sometimes wonder about this - all these special numbers that we find become uninteresting in other bases than decimal. When moving to hexadecimal, new opportunities open. We used to use hex 0xFEEDBEEF as a meaningful number when debugging. For non-programmers, zero is often used as a default value for a variable with no particular initial setting, but zero is found so commonly that it is not useful. Of you set the initial value of an unassigned variable to 0xFEEDBEEF, it pops out at you should your program try to use it without calculating an initial value.
Now there are truly interesting numbers. For example, primes are prime and squares are squares, regardless of the base used. And there are interesting bases other than 10 - consider logarithms that use e. But a lot of numerology and "interesting numbers" are just quirks of our ten digits.